640157326 has 4 divisors (see below), whose sum is σ = 960235992. Its totient is φ = 320078662.

The previous prime is 640157311. The next prime is 640157351. The reversal of 640157326 is 623751046.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a junction number, because it is equal to n+sod(n) for n = 640157291 and 640157300.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160039330 + ... + 160039333.

It is an arithmetic number, because the mean of its divisors is an integer number (240058998).

Almost surely, 2^640157326 is an apocalyptic number.

640157326 is a deficient number, since it is larger than the sum of its proper divisors (320078666).

640157326 is a wasteful number, since it uses less digits than its factorization.

640157326 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 320078665.

The product of its (nonzero) digits is 30240, while the sum is 34.

The square root of 640157326 is about 25301.3305183739. The cubic root of 640157326 is about 861.8444845174.

The spelling of 640157326 in words is "six hundred forty million, one hundred fifty-seven thousand, three hundred twenty-six".